The attacker is a user from the image file in the above scenario. A file system is a method or structure that organizes and stores files and data on a storage device, such as a hard disk, a flash drive, etc. A file system can have different types based on its format or features, such as FAT, NTFS, ext4, etc. A file system can be analyzed to extract various information, such as file names, sizes, dates, contents, etc. A Linux image is an image file that contains a copy or a snapshot of a Linux-based file system . A Linux image can be analyzed to extract various information about a Linux-based system or device . To analyze the file system of a Linux image captured from a device that has been attacked recently and identify a user from the image file, one has to follow these steps:
Navigate to Documents folder of Attacker Machine-1.
Right-click on Evidenced.img file and select Mount option.
Wait for the image file to be mounted and assigned a drive letter.
Open File Explorer and navigate to the mounted drive.
Open etc folder and open passwd file with a text editor.
Observe the user accounts listed in the file.
The user accounts listed in the file are:
root:x:0:0:root:/root:/bin/bash daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin bin:x:2:2:bin:/bin:/usr/sbin/nologin sys:x:3:3:sys:/dev:/usr/sbin/nologin sync:x:4:65534:sync:/bin:/bin/sync games:x:5:60:games:/usr/games:/usr/sbin/nologin man:x:6:12:man:/var/cache/man:/usr/sbin/nologin lp:x:7:7:lp:/var/spool/lpd:/usr/sbin/nologin mail:x:8:8:mail:/var/mail:/usr/sbin/nologin news:x:9:9:news:/var/spool/news:/usr/sbin/nologin uucp:x:10:10:uucp:/var/spool/uucp:/usr/sbin/nologin proxy:x:13:13:proxy:/bin:/usr/sbin/nologin www-data:x:33:33:www-data:/var/www:/usr/sbin/nologin backup:x:34:34:backup:/var/backups:/usr/sbin/nologin list:x:38:38:Mailing List Manager:/var/list:/usr/sbin/nologin irc:x:39:39:ircd:/var/run/ircd:/usr/sbin/nologin gnats:x:41:41:Gnats Bug-Reporting System (admin):/var/lib/gnats:/usr/sbin/nologin nobody:x:65534:65534:nobody:/nonexistent:/usr/sbin/nologin systemd-timesync:x:100: systemd-network:x: systemd-resolve:x:systemd-bus-proxy:x: syslog:x: _apt:x: messagebus:x: uuidd:x: lightdm:x: whoopsie:x: avahi-autoipd:x: avahi:x: dnsmasq:x: colord:x: speech-dispatcher:x: hplip:x: kernoops:x: saned:x: nm-openvpn:x: nm-openconnect:x: pulse:x: rtkit:x: sshd:x: attacker::1000
The user account that is not a system or service account is attacker, which is a user from the image file.
